Date of Graduation


Document Type


Degree Name

Master of Science in Animal Science (MS)

Degree Level



Animal Science


Jeremy G. Powell

Committee Member

Fred D. Clark

Second Committee Member

Kelly M. Loftin


Histomonas meleagridis, Turkey, Commerical farms, Arkansas, Oklahoma


Histomonas meleagridis, is a parasitic protozoan, commonly found in the gallinaceous species of birds and is the causative agent of Blackhead disease. The cecal worm, known as Heteraskis gallinarum, acts as a vector in the spread of H. meleagridis in gallinaceous birds. H. meleagridis develops inside the cecal worm and in its eggs which allows H. meleagridis a method to survive in the environment. Blackhead disease causes high mortality rates in both chickens and turkeys; however, turkeys are noted to have a higher mortality rate compared to chickens. Molecular diagnostic testing such as PCR has been developed by creating primers for H. meleagridis allowing producers to identify disease reservoirs for the Blackhead disease. Also, ELISA testing for antibody production can be used as a tool to confirm outbreaks of histomoniasis in turkey flocks that may or may not be showing symptoms. Current options for producers to control the disease on their farms include following biosecurity protocols, applying litter acidification additives, and placing lime on the ground around the outside of production barns. These methods used by the farmers do not effectively stop the spread of H. meleagridis in the flocks. Therefore, determining other possible vectors that can spread the disease on the farms, could help the producers in controlling histomoniasis. For this study, insects were collected on three farms in Arkansas and one farm in Oklahoma. These insects were sorted out by species before PCR was performed. First, the insects were tested to see if DNA was present and then tested to see if H. meleagridis was present. Based on the study, no insect tested contained H. meleagridis.